I ran a file to export which converts to a quicktime .mov file. 6:12 MB 8:40 MBA I expected these times but what's nice is that the fans on the MB kick in at full blast in 1 minute whereas the MBA full fans at 4 minutes full. Far less fan noise on the MBA! Looking at the temps, the MBA ran a full 11 degrees cooler the entire time. Fan noise is very important as I can now record voice from a usb mic without the fan noise being recorded as was the case with the Macbook. Only downside is that the MBA takes longer (didn't time it) to cool down. Does anyone else have a longer than usual cool down time for the fans to go from full 6500 rpm to the norm 2500rpm?